“White House Down” had its big Washington premiere in Georgetown on Friday night with all the major stars present. This is the one where Tatum is the police officer who must rescue President Jamie Foxx when the bad guys blow up the White House (and we are assured that this is a completely different movie than Gerard Butler trying to save President Aaron Eckhart in “Olympus Has Fallen”). Don’t remember it filming in D.C.? Yeah, well, that’s cause it was mostly done in Montreal, as usual.